Endocrine Abstracts

Colour-Doppler Ultrasonography (CDU) is applied to the study of many thyroid diseases. In the last one semiquantitative (colour-signal) and quantitative (peak flow velocity at inferior thyroid artery) evaluations are considered. Graves’ disease (GD), amiodarone-induced thyrotoxicosis were better characterized, even Hashimoto thyroiditis and De Quervain thyroiditis were studied. We described a case of Silent Thyroiditis (ST), showing the possibility to distinguish it from GD.

A 27-year-old woman was referred to us, with thyrotoxicosis arisen after 3 months from delivery. Very low TSH (0.05 mUI/ml, n.v. 0.30–4.10), high FT4 (23.5 pg/ml, n.v. 8–18), high FT3 limits (5.98 pg/ml n.v. 2.20–5.50). We have performed a CDU evaluation with an ATL-HDI-5000 sonographic system; a 5–12 MHz linear array probe was used on the power Doppler imaging mode. Echo demonstrates a diffuse hypoecoic, homogeneous ecopattern; CDU shows an absence of colour-signal (class 0). After eight weeks the symptoms remitted, TSH was slightly elevated (21 mUI/ml), FT4 slightly low (7 pg/ml) and FT3 came back into normal limits. At CDU the colour signal reappeared (class 2).

In this study the first observation with CDU about a case of PPT is reported.

PPT belongs to the lymphocytic thyroiditis where the autoimmune process is caused by cell-mediated reaction, bearing a destructive process precipitated in post-partum period. We observed the time-course of disease by CDU. During thyrotossicosis-phase the colour-signal was absent and reappeared in following phase of primary hypothyroidism.

PPT can represent a challenged diagnosis, because it is difficult to differentiate it from GD during post-partum: differential diagnosis is important for different time course and therapy of two forms. On the other hand scintiscan may be hazardous. CDU could show itself an accurate tool to this purpose: showing a pattern of colour signal 0, it can be useful to suggest a form of PPT, instead of GD where the colour signal is very much increased.